Fred J. Christensen, at 84; World War II flying ace

To make a point to fellow fighter pilots in World War II, Fred J. Christensen always flew with Sinbad, a stray black cat he had found.

Seeing him return safe from combat missions -- black cat and all -- helped motivate the other pilots, his daughter Diane Haagensen said yesterday.

And counter to traditional superstitions, Sinbad was very good luck for her father, who shot down 22 Nazi planes during the war, including six in a two-minute span of one air battle.

Colonel Christensen, who the Massachusetts Air National Guard said was believed to be the last living US ace from World War II, died Tuesday in the Beaumont of Northborough skilled nursing center. He was 84 and was being treated for complications from diabetes.

Though he flew 107 combat missions against the German Luftwaffe, ''he was a very humble man," his daughter, an East Falmouth resident, said in a telephone interview. ''He didn't want to be known as a war hero."

Colonel Christensen ''was happy for the opportunity to speak with people, especially children, because he wanted them to know about history and that wars were not always good things," she said, ''because people had to make sacrifices and their families had to make sacrifices."

His older brother, also a pilot, died during the Korean War -- a loss Colonel Christensen never got over.

Colonel Christensen had studied at Harvard and the Massachusetts Institute of Technology in the nascent days of World War II and sought to join the military after Germany invaded Norway, where his ancestors were from and his extended family lived.

He had always wanted to fly.

''From a very early age, he did anything he could to get to the airport or befriend those at school whose dads had planes," his daughter said, adding, ''As children, we thought he could fly without wings."

A second lieutenant and captain in the Army Air Corps, he flew P-47 Thunderbolts with the 56th Fighter Group -- Colonel Hubert ''Hub" Zemke's Wolfpack -- and shot down six enemy planes on July 7, 1944.

One time, a reporter and photographer arrived to do a feature on the Wolfpack. When the photographer tried to get a picture of Sinbad, the cat kept leaping among the packed parachutes. That day, Haagensen said, all the pilots whose gear Sinbad had touched returned with air victories, increasing the cat's legend.

Sinbad returned to the United States with Colonel Christensen after the war and lived with his family -- as did a few generations of the cat's descendants.

Back home, Colonel Christensen initially took a part-time job flying with the Air National Guard and studied music at Boston University. He played piano and clarinet, and loved jazz.

''Then I came along, and he needed a job to support everybody," his daughter said, so he took a job flying full time with the Guard.

In 1961, he began flying with the Air Force Reserves, where he remained until he retired as a colonel in 1971.

For his service in combat, he was awarded some of the most prestigious medals, including the Distinguished Flying Cross, the Silver Star, and the Air Medal.

He lived for many years in Wayland and Watertown and, as with Sinbad, continued to scoop up wayward animals.

''He used to bring home animals that he found on the runway," his daughter said. ''Owls, seagulls, turtles -- they would live on our screened porch until they were healed or escaped."

Colonel Christensen, she said, also was devoted to his three daughters.

''He was a father before his time in that he spent a lot of his non-working hours with us," she said. ''He especially liked to take us to the ocean, or skiing in the winter."

His love for his family also prompted him to keep an eye out when he was working.

''He used to fly over our house at a very low altitude and dip his wings," his daughter said. ''Daddy's up there -- he's looking out for you."

In addition to his daughter Diane of East Falmouth, Colonel Christensen leaves daughters Elaine of Upton and Janine of Wayland; two grandsons; and two great-grandchildren.

A graveside service with military honors and a missing man flyover salute will be held today at 12:30 p.m. at Massachusetts National Cemetery in Bourne.